ANDROID UPDATE:
I made an Android version: www.thomasbowker.com/vol/android
Though for the best experience play it on a PC.

Note: About the theme, about halfway through development I realised my grander ideas for the AI just weren't feasible. So I decided to keep it simple and polish the game, since I prefer to make a more playable game than a worse one that conforms to the theme more. Thanks for playing!

IF YOU WANT TO CHANGE KEY SETTINGS:
Download either the Win or Mac version and change the input settings in the pop-up.

I think it gave me a bit of an headache with the bright colors passing by the screen so fast :P Other than that, nice little game, especially the effects were cool(when enemy damages you and the transitions in the menu).

fantastic job! garish colors, blurring effect on being attacked, rudimentary sun, synth music, merging enemies, the burbling sound enemies make to alert you to their presence, control scheme--love it all.